Control device for furnace gases in hot water boilers



Feb. 23, 1965 J. FRANZEN 3,170,419

CONTROL DEVICE FOR FURNACE GASES IN HOT WATER BOILERS Filed Feb. 15, 1963 CONTROL DEVICE son FURNACE oAsss 1N nor WATER BOILERS John Franzen, Askersund, Sweden, assignor'to John Axel Franzen, Askersund, Sweden Filed Feb. 13, 1963, Ser. No. 258,247 Claims priority, application Sweden, Mar. 15, 1962,

V ,872/ 62 1. 6 Claims. 7 (Cl. 110-97) .This invention relates to an improved controlgdevice for furnace gases in hot water boilers equipped with sectional heating elements, tubes and the like. The inven-. tion refers particularly, without being restricted thereto,

to the type of upright central heating boilers in whlchthe sectional heating elements, tubes and the like are in an assembly disposed in parallel space relationshipwitlnn a heating chamber for the flow of hot furnace gases between the same with the object of heating the circulatory water for room-heating elements andthe like in a house.

It isan object of this invention toprovide a device in the water ,heating elemnt assembly per se to direct the stream of hot furnace gases to restricted portions of the assembly especially at low fueling of the boiler.

Another object of the invention is to provide a device in the water heating element assembly per se to concentrate the stream of hot furnace gases to a central narrow istream within the assembly especially at a low fuehng of the boiler.

. the hot stream of the gas'esflfrom by-passing the assembly attire-entrance of the same.-

1 Still a further object of the invention is to provide a .devicetoraise the temperature of the furnace gases at a low'fueling' of the boiler and prior to their entry into the water heating element assembly.

With these and other objects in view, theinvention es- United States Patent ice d 2.. water. The hot waterpips 5 are of a broadly flattened shape as shown in FIGS. 1 and 2, and are arranged in parallelism providinga space 7 therebetween as shown in FIG. 2. Normally all of the hot Water pipes are of the samegauge, and for practical purposes, the width of the spaces 7 is also the same. i d I a When mass-producing boilers of various sizes, the hot water pipe assembly isformed in its, entirely by joining together a numberof single sections, in which case, each section consists of a portion of the lower and upper junction boxes 4 and 6 including the pipebetween the two boxes. v I 1 i I The flow control device according to theinvention is disposed within the heating element, assembly-and its chamber 2, and in theembodi-ment shown two guide plates or deflectors 8 and 9 set with synchronized movements of adjustment opposite each other andextending on each side of the pipe assembly for the entire longitudinal directionof the same. the openings of the spaces 7 between the various sections or pipe rows if such are usedand are preferably of the somewhat bent form as shown in FIG. 1. The deflectors 8 and 9are journalled on shafts 10 and 11 respectively, and each deflector can be turned towards or away from the heating elements by means of a control-handle located, exterlorly of the boiler. The control movement is in opposite directions, and by means of which the deflectors can be simultaneously .adjustedin a'direction towardsor away from the heating element assembly.

In FIGS 1- and 2, the deflectors 8 and 9 are in the I. form of a comb, with teeth 15 and-16' respectively, which 7 caseforms a narrow passage for the flow of thefume's.

sentially is characterized by the provisionof a device in q the waterheati'ng element assembly j'per se, said device consisting of a number of 'dellectorsfor changing the direction'of the hot furnace gases within the assembly and capable of being adjusted in such'a manner that the jcross area of the stream path within the assembly per se.

through .which thehot furnacesgases normally have to] pass can be reduced as required in the actualspaces bei tween the assembled hot water pipes. 4-

An embodiment of the invention'is illustrated in the accompanying drawing, i'n which:

FIGURE 1 isa View partly inside elevation and' partly. in cross section of theheating elementassem'bly,

FIGURE 2- is a fragmentary front viewYof same,'ancl 1 FIGURE 3 is a side View partially in elevation and partlyin cross sectionof a hot water boiler'equipped with aiheating element assembly. I The heating element asssembly '1 for the-hot water sup plyis disposed in a chamber 2 within, the boiler along side fuel storage-chamber 28 and above a further cham' tion fumes and smoke gasesnenter-the chamber 3, herein referred to as the flame chamber. The upward flowing fumes from'the flame chamber first pass a lower-junction is also possible to guide the same to pass 'a separate heatingarrangement for the supply-of separate dish-or bath her 3 at the side of furnace 29 from which the'combusq In the transverse direction of the deflectors, the lengthof the teeth is such that when the deflectors are set in their closed position, there remains only a slight opening 17 of predterrnined size,.'or no? opening, between any two teeth set in position from either side, and thus in the first Wide or narrow centrally disposed opening'for the flow Of theifumes inside the heating element assembly can thus be established simply by varying the'arnount of movement. of the teeth.

As shown in FIG. 1, there are open space '13 and 19 along thelboiler wan on either side of the heating ele-I ment assembly, .in which spaces the'deflectors 8 and 9 a are pivotally arranged and through which the fumes canpass by the heating element assembly when the defiectors-are set in the open position; Since there are spaces between. the teeth of the deflectors, it is evident vid'ed with additional deflecting plates or screens 20" and 21 respectively, located 'at a position close to the shafts 10 and 11, and directed towards and approximately reaching the heating element assembly whenthe deflec tors are in the fully closed 'positionfi Somewhat higher;

each sectionalheating'element assembly has been pro- .vided'with a fixed outwardly extending deflecting plateor screen 22 and 23 respectively, the length of which i ,v

such that on'setting. the "deflectorsin such a ppsition that the plates 20 and 21 coincide with the fixed plates 22 and 23,'the ends of the deflector platesfwill besetlso; closely in line that the openflue is blocked, and the f hot fumes areforced in'between the sections of the heatf The deflectors. face v ing element assembly. Thesereenshave the same length as the deflectors in the length direction of the assembly. Alternatively, the fixed plates .22 and 23 may be bent; or assume; an angular shape forming a bracket with side pieces 22a and 23a being so positioned that the free ends of the movable plates and 21 will pass along the side pieces. when the deflector position is being changed for the purpose of forcing the fumes to pass through the space-between the sections of the heating element assemblythereby preventing heat, loses irrespective of the particular position of the deflectors- The arrows in FIG. 1 indicate the direction of flow of the fumes when the mizers.

deflectors 8 and 9 areturned fully inward; J

Since, according to the extent of actuation, the deflectors thus greatly assist in preventing the fumes from by-passing the heating elements ,at the opening edges between the same and the wall, the fumes will be more and more con ment assembly. In'espective of the fueling of the boiler and thecorresponding throttling of the fumes, this results in the passing fumes giving off their heat content to the elements to an increasing extent while at the same-time achieving a suitable exhaust temperature, a moreeflicient heat exchange rate, and a more favorablegfuel economy.

This also implies that the exhaust temperature of'the fumes on low fuel consumption of the boiler can ,be raised by .opening the deflectorsso that sweating and erosive action on the Walls of the boiler and chimney flue can be avoided. The duplex type of deflector arrangement will also establish a more symmetrically improved distribution of thezthermal strains and stresses.

It is obviously of great importance that the fumes have the highest attainable temperature when striking the heating element, and particularly so on low fuel consumption when the deflectors cause the fumes to be compressed into a central column at theheating element. High initial temperature will in every case produce a high heat exchange centr-ated toward the central position of the heating elerelationship. Instead of the fixed screening plates 22- within the chamber for supplying hot circulatory Water for heating rooms and like purposes, "and control-means Within the: chamber for the hot furnace gasesQsaid water heating element including a plurality of broadly flattened tubes having opposite ends, said tubes being arranged in spaced apart'parallel relationship and being of a width less than the distance between opposite wallmeansof the chamber for providing spaces within'the chamber at each endof the heating element, water dividing and water collecting boxes connected to the opposite ends-of the tubes; said control means including a"deflector plate 7 passing through the chamber are caused to move inwardly mounted in the space ingthe chamber at each end of the heating element intermediatesaid boxes and essentially disposed in the spaces between the tubes so that gases of the tubes adjacent one of the'boxes, then axially of the co-efficient as well as favorable heating economy. In this particular case, the best result can be obtained by combining with the deflector arrangement a set of heat retaining red 'hot glow bodies 26 :of castiiron-or other suitable material which is disposed .in the passage between the furnace and the flame chamber 3. Such glowing bodies are. capable of storing heat even under low fuelingconditions and contribute greatly to increasingthe temperature of the fumes;

In the case of upright boilers of considerable height, a 1 pluralityof deflector sets may be arranged one above the other and adapted for manual control as in the embodiment described above, or automaticallycontrolled by heating element sweepingthe surfaces of the tubes in the spaces between the tubes and thence outwardly of'the tubes adjacent the other box, and means movably mountingsaid platesin'said spaces in the chamber for; adjusting the cross-sectional area of the axial path of the gases in the heating element. V

2. The heat exchange assembly as claimed in-claim l, in which said deflector plate is provided with spaced teeth substantially corresponding in width to the width of the spaces between said tubes adapted to enter the spaces between said tubes. I.

3. In a heat exchange-assembly, wall'means defining a chamber, a furnace,means for passing hot furnace gases through the chamber, a w ater heating element located within the chamberv for supplying hotcirculator y' water for heating rooms and like purposes, and controlmeans within the chamberfor the hot furnace gases,= said water heating eleinentincluding a plurality. of broadly flattened tubes-having opposite ends, said tubes being'a rranged in spaced apartav parallel relationship and being of a Width a, thermostat. The'boiler may be equipped-with anoil burner as indicatedat 27 in FIG. 3,:or with the necessary fittings for the installation of such a'burner, thus offering I alternative methods of firing.

Due to-the collection of soot in the heating element,

the teeth 'of'the deflectors are dimensioned with .a certain amount ofplay' in the spaces between the sections.

Sincethepassing of finnesiat'theserpoints is considered inappropriate. on=extremelylow fueling conditionsfstop ledges orabutments'31 and 32 have been fixedly attached to. the sections forthe teeth 15 and-16 intheir innermost closing position. .Apart from restricting ,the movement of the teeth, the ledges close the gaps which may provide for play, and.thusprevent the passing-of fumes at the most limitedareaof flow between the deflector'teeth.

The deflector control arrangements have been. so designed that they are capable of adjustment when'thev boileris in operation. The same can, by'means of their foot holders, be locked in position andthus prevented from being inadvertently moved from a position previous-1 ly'foundto be favorable froma' heat economical point of vieweven if thegl'deflector' plates must be removedfor cleaning orthelike; V g p Although vertical tu'besare preferred, horizontal tubes may be used with'the same being disposed in superposed less than'the distance. between opposite wall'means of the chamber for providing spaces within the chamber at eachend of the heating element, water-dividing and water collecting boxes'connected to'the opposite ends of the tubes, said control means including a deflector plate positioned the space in thechamber atveach end of the heating ele- -ment intermediate. said boxes, each'of said plates being provided with teeth corresponding inv width to the spaces between said tubes and adaptedto be disposed in such spaces so that gases passingthrough'the chamber are caused to movezinwardly of the :tubes adjacent one .of the boxes, then axially of the heating element sweeping the surfacesv of the tubes insuch'spaces and thence. outwardly of the tubes adjacent the other. box, a shaft' in the a space ateachend of the heating element. on which the deflector plate ispivoted, means for simultaneously ad-r V justing. said plates, such means including a link,"further link means connected to'each shaft and extending radial-' ly -therefrom in opposite directions, andmeans coupling said link to said fu'rther-link means whereby actuation of the link simultaneously moves said plates toward or, away from each other.

4. The-heat exchange assembly as, claimed in claim 3,: a further including screen means p'r'ovid'edfor each deflector 'plate in proximity t'osaid shaft with such screenmeans being directed towards said heating element with the free end thereof closely adjacent the ends. of said tubes;

when the deflector plates are moved to their extreme position towards said heating element for preventing bypassing of the furnace gases at such ends of the tubes.

5. The heat exchanging assembly as claimed in claim 4, including a stationary screen attached to each end of said heating element and directed towards the deflector plate so that when the deflector plates are in their positions adjacent the heatingelement the free end thereof coacts with the free end of the movable screens.

6. The heat exchange assembly as claimed in claim 1, further including a plurality of heat retaining glow bodies located between the furance and said chamber for elevat- 7 ing initial temperature of the furnace gases prior to the entrance thereof into said chamber.

References Cited by the Examiner UNITED STATES PATENTS 2,070,223 2/37 Butler 16596 2,083,745 6/37 Risdon 126-101 $540,359 2/51 Torpy et al 110-97 10 JAMES W. WESTHAVER, Primary Examiner.

FREDERICK KETTERER, Examiner. 

1. IN A HEAT EXCHANGE ASSEMBLY, WALL MEANS DEFINING A CHAMBER, A FURNACE, MEANS FOR PASSING HOT FURNACE GASES THROUGH THE CHAMBER, A WATER HEATING ELEMENT LOCATED WITHIN THE CHAMBER FOR SUPPLYING HOT CIRCULATORY WATER FOR HEATING ROOMS AND LIKE PURPOSES, AND CONTROL MEANS WITHIN THE CHAMBER FOR THE HOT FURNACE GASES, SAID WATER HEATING ELEMENT INCLUDING A PLURALITY OF BOARDLY FLATTENED TUBES HAVING OPPOSITE ENDS, SAID TUBES BEING ARRANGED IN SPACED APART PARALLEL RELATIONSHIP AND BEING OF A WIDTH LESS THAN THE DISTANCE BETWEEN OPPOSITE WALL MEANS OF THE CHAMBER FOR PROVIDING SPACES WITHING THE CHAMBER AT EACH END OF THE HEATING ELEMENT, WATER DIVIDING AND WATER COLLECTING BOXES CONNECTED TO THE OPPOSITE ENDS OF THE TUBES, SAID CONTROL INCLUDING A DEFLECTOR PLATE MOUNTED IN THE SPACE IN THE CHAMBER AT EACH END OF THE HEATING ELEMENT INTERMEDIATE SAID BOXES AND ESSENTIALLY DISPOSED IN THE SPACES BETWEEN THE TUBES SO THAT GASES PASSING THROUGH THE CHAMBER ARE CAUSED TO MOVE INWARDY OF THE TUBES ONE OF THE BOXES, THEN AXIALLY OF THE 